This feature is available to authenticated users only.

Tina Wammer, Per Olof Lundmark; Using OCT and a novel grading method to investigate the prevalence and severity of epiretinal membranes in an optometric practice in Norway. Invest. Ophthalmol. Vis. Sci. 2015;56(7 ):1818.

Purpose:
The introduction of OCT in optometric practice has improved detection and diagnosis of epiretinal membranes (ERM). However, the occurrence of ERM in Norway is unknown. In this cross-sectional study, we investigated the prevalence and distribution of ERM stages imaged by OCT in optometric patients.

Methods:
120 healthy patients, age > 50 yrs, were enrolled from one optometric practice in Trondheim, Norway, during a period of 6 months. All underwent a full optometric examination followed by SD-OCT (Topcon 3D OCT-2000). Repeated volume scans (128 B-scans, 512 A-scans) were obtained from the posterior pole of both eyes. ERM was identified (I), classified (C) and graded (G) based on: I) the occurrence and extension of hyperreflective bands, C) location of ERM relative to the fovea (fovea, parafovea, macula), and G1) any concomitant deformation of the underlying retinal structures (with and without involvement of the receptor layer) and G2) deformation of the foveal profile (2 levels of flattening, 2 levels of steepening).

Results:
4 months into the study 182 eyes of 91 patients were included (F: 64, mean age 66.5 yrs). The prevalence of ERM in one or both eyes was 30.8 % (CI 21.3 - 40.3) and 7.7 % (CI 2.2 - 13.2), respectively. Patients with ERM were significantly older than patients with no ERM (+ 9 yrs, p < 0.001). However, both genders were equally affected. Among eyes with ERM the distribution of foveal-, parafoveal- and macular ERM (C) were 8.6 %, 42.9 % and 100.0 %, respectively. Retinal deformation without receptor layer involvement (G1) was found in 68.6 % of these eyes. None showed signs of receptor layer involvement. 42.9 % of the eyes with ERM had deformed foveal profiles (G2) ranging from slightly- (17.1 %) to markedly flattened (8.6 %), or from slightly- (8.6 %) to markedly steepened (8.6 %). The frequency of ERM classified as foveal was 12.5 % for eyes with deformed retina and 26.7 % of eyes with both deformed retina and foveal profile.

Conclusions:
This is the first report on the prevalence and severity of ERM imaged by OCT in optometric patients in Norway. Results indicate that ERM imaged by OCT may be encountered more frequently than expected from the literature, however with limited involvement of the retinal structures and foveal profile. Further studies to understand the implications for monitoring in optometric practice is warranted.